"Arson's going to have to check it out," said Leger, executive aide to fire Commissioner Joseph A. Conant.

The commissioner was among the emergency officials who responded to the two-alarm fire shortly before 2 a.m. at 495 Chestnut St., the scene of a massive brick building that smoldered and belched smoke into the humid air as firefighters attacked the blaze from Chestnut and Prospect streets.

09.03.2013 | SPRINGFIELD -- Demolition was underway Tuesday morning at the former Chestnut Street Junior High School, which sustained heavy damage in an overnight fire.Mark M. Murray | The Republican

A fire lieutenant sustained an unspecified injury and was treated at Baystate Medical Center and later released, Leger said.

The vacant structure was severely damaged and its future is uncertain. "Floors are burnt right through," Leger said. "There was a large amount of fire in the back of the building."

Flames could be seen shooting from boarded-up windows at the front of the 4-story building on Chestnut Street, while thick smoke rose high above the rear of the structure on Massasoit Street.

Fire officials began investigating reports of smoke in the Memorial Square section of the North End at about 1:45 a.m. Within minutes they pinpointed the smoke to the Chestnut Street school, bounded roughly by Prospect and Ringgold streets on the north and west and Massasoit and Carew streets on the east and south, respectively.

The call was issued at about 1:50 a.m., with the arson unit dispatched immediately afterward. It was followed by a "working fire" declaration at 1:55 a.m.

Residents of a Prospect Street apartment building were evacuated as a precaution, and city police cruisers blocked key intersections near the building to accommodate fire crews.

The 82,000-square-foot building, which was built in stages beginning in 1901, has lay dormant since 2004, when then-mayor Mayor Charles V. Ryan, citing a rotting gymnasium floor and other hazardous conditions, ordered the building closed. Two alternative education programs -- the Springfield Academy and the Springfield Adolescent Graduate Experience -- were relocated. Since then, the building has suffered additional interior damage and deterioration.

Records list the building's owner as the City of Springfield / Springfield Academy. The assessed value of the building and land was $5,001,300.

In May 2011, the New England Farm Workers Council was named preferred developer by the city, but that designation expired.

A year later, city officials sought redevelopment proposals for the building, touting its prime location in the middle of Springfield's health care corridor between Mercy and Bay State medical centers.

The future of the large building, now heavily damaged by fire, smoke and water, remains uncertain. The nearly city-block-long property is enclosed by a chain-link fence with no-trespassing signs.

Carlos Ramos, a neighborhood resident who grew up near the corner of Allendale Street, recalled playing handball at the school during his years there as a student.

"It's sad. There's a lot of memories here," Ramos said as he watched the firefighters work, noting that a number of his family members also attended the school.

"I wish they could have done something better with this place," he added.

Leger said the fire is "definitely" suspicious, particularly since the building's electricity, gas and other utilities were turned off well before Tuesday's fire. He estimated it would cost half a million dollars to tear down the compromised structure.

Other North End fires, including one about two weeks ago at an abandoned property across from the old junior high, have ratcheted up concerns that an arsonist is at work.

The Aug. 15 fire at an abandoned home at the corner of Chestnut and Allendale streets, just north of the school, also has been deemed suspicious, according to officials.

Leger urged anyone with information about the fire at the school to call the Springfield Arson & Bomb Squad at (413) 787-6370.

Meanwhile, fire officials announced at 6:30 a.m. that they would be at the Chestnut Street fire scene for "several more hours." During this time, Chestnut is expected to remain closed to traffic between Carew Street and Brookline Avenue, while Prospect Street will remain closed between Chestnut and Massasoit streets.